Inlet air way control structure of air tool

ABSTRACT

An inlet air way control structure of an air tool includes a valve sleeve mounted on an inlet channel inside the air tool and communicated with a first inlet air way and a second inlet air way, and a control shaft penetrating the valve sleeve, thereby the control shaft can change the inlet air way of the air tool so that the air tool can be controlled to have a clockwise or counterclockwise rotation. Moreover, the valve sleeve has a fixing element for being fixed with the cylinder, and thus the inlet air way control structure of the present invention can be applied to a plastic housed air tool. Furthermore, owing to the control shaft, the user can operate the rotation direction of the air tool by only one hand so as to achieve a great convenience.

FIELD OF THE INVENTION

The present invention is related to an inlet air way control structure of an air tool, and more particularly to a plastic housed air tool having a fixing element mounted on a valve sleeve for fixing with a cylinder.

BACKGROUND OF THE INVENTION

Usually, conventional air tools use pressed atmosphere to drive the air motor inside an air tool set so as to provide all kinds of operations of the air tool, wherein the air motor set can have a clockwise or a counterclockwise status through controlling the air inlet direction of the pressed atmosphere. For example, R.O.C. Patent Publication No. 569885 “Improved structure for air way control mechanism” disclosed an improvement for the air way control mechanism including a cylinder which has a column cylinder barrel, an air chamber located inside the cylinder barrel, and two directional air holes passing through two corresponding walls at one end of the cylinder for communicating the air chamber with the outside of the cylinder barrel; an air valve which has a circular body rejecting to an axial facet of the cylinder barrel through an axial facet thereof, and two extending air holes mounted on the body and extended along a predetermined direction respectively, wherein the openings of the holes are respectively located on an axial facet of the body and the inner circular surface of the body, and the two opening on the axial facet of the body are communicated with the two directional air holes respectively; and an adjusting element which has a plate-like base coaxially accommodated in the body, capable of pivoting between a clockwise and a counterclockwise statuses, and rejecting to the inner circular surface of the body through a peripheral facet thereof, an inlet channel along a radial extension of the base, and an outlet which is the opening of the inlet channel at a predetermined position on the peripheral facet of the base for communicating the inlet channel with a corresponding extending air hole.

According to the description above, the pressed atmosphere passes through the inlet channel of the adjusting element and enters the clockwise direction air hole via the extending air hole above the air valve. It is noted that the pressed atmosphere means the pressure thereof is higher than the normal atmospheric pressure so that an air way might be generated owing to a pressure balancing between the different pressures of the pressed atmosphere and the environmental atmosphere, and this is namely the principle that the air tool drives the motor set. However, in fact, there is a problem existed in the above-described patent, that is, the adjusting element for controlling a clockwise or counterclockwise rotation of the air tool is mounted at the rear end of the whole body of the air tool. According to this, it is obvious that the user may have difficulty in operating the tool and controlling/changing the rotation direction of the air tool at the same time. This is quite inconvenient for the user, whose both hands always have to respectively hold the air tool and the processing object, and also causes a low operation efficiency.

Therefore, how to effectively transmit the pressed atmosphere and also facilitate the operation of the user is namely the purpose of ones skilled in this technology. Accordingly, the present invention discloses a new designed air tool through which the user can operate only by one hand, that is, the holding of the tool and the controlling of ON/OFF and rotation can be achieved at the same time so that an operation convenience is also presented.

SUMMARY OF THE INVENTION

One object of the present invention is to provide an inlet air way control structure of an air tool which can change the inlet air way for controlling a clockwise or counterclockwise rotation of the air tool.

Another object of the present invention is to provide a better operation convenience of the air tool so that the user can, by only one hand, hold the tool and control the ON/OFF and rotation direction at the same time, which is also suitable for the plastic housed air tool.

For achieving the objects above, the preferred embodiment of the present invention provides a valve sleeve mounted on an inlet channel inside an air tool and communicates with a first inlet air way and a second inlet air way, and a control shaft penetrating the valve sleeve, wherein the control shaft has a separating portion and a first conducting portion and a second conducting portion respectively located at two sides of the separating portion, and the control shaft can have a movement inside the valve sleeve so as to selectively locate in a first position for coupling the inlet channel to the first conducting portion and communicating with the first inlet air way, or at a second position for coupling the inlet channel to the second conducting portion and communicating with the second inlet air way, thereby a clockwise or counterclockwise rotation of the air tool can be controlled by the control shaft changing the inlet air way of the air tool. Furthermore, the valve sleeve has a fixing element for being fixed with the cylinder, and thus the inlet air way control structure of the present invention can be applied to a plastic housed air tool.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of this invention will be more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 shows a structural drawing of a preferred embodiment in the present invention;

FIG. 2 shows a sectional drawing of a preferred embodiment in the present invention;

FIG. 3 shows a sectional drawing of a preferred embodiment in the present invention; and

FIG. 4 shows a sectional drawing of a valve sleeve and a cylinder in a preferred embodiment according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Please refer to FIG. 1 which shows a structural drawing of a preferred embodiment in the present invention. As shown in FIG. 1, this embodiment of the present invention includes an air tool 10 which has a handle 11 and an inlet 12 located in the lower end of the handle 11. The inlet 12 provides a pressed atmosphere into an inlet channel 13. The inlet channel 13 has a valve shelve 14 mounted thereon and also has a first inlet air way 131 and a second inlet air way 132. The valve sleeve 14 has plural through holes 141, 142, 143 mounted thereon respectively connected to the inlet channel 13 and the first and the second inlet air ways 131, 132, and the peripheral of the through holes 141, 142, 143 has a resin pad 20 for avoiding leaking. The first inlet air way 131 and the second inlet air way 132 are communicated with a cylinder 15 inside the air tool 10 and the first and the second inlet air ways 131, 132 are respectively the clockwise and the counterclockwise inlet way of the cylinder 15 so that through different inlet directions, a rotor 16 inside the cylinder 15 can be controlled/changed so as to drive a transmission shaft 17 to rotate clockwise or counterclockwise. Further, an air capacity button 18 connected with the cylinder 15 is mounted at the rear end of the air tool 10 for controlling the inlet volume so as to adjust the rotation speed of the rotor 16 and the transmission shaft 17.

A control shaft 30 is mounted inside the valve sleeve 14, and both the valve sleeve 14 and the control shaft 30 are mounted below the cylinder 15 and parallel to the cylinder 15. The control shaft 30 has a separating portion 31 whose outer diameter is equivalent to the inner diameter of the valve sleeve 14, and on the control shaft 30, an airtight ring 34 which tightly matches the inner wall of the valve sleeve 14 is provided for preventing the pressed atmosphere from leaking, and a first conducting portion 32 and a second conducting portion 33 which are respectively located at two sides of the separating portion 31 are provided for passing through the air. At the two ends of the control shaft 30, a rejecting portion 35 exposed out of the valve sleeve 14 is provided, and the rejecting portion 35 is penetrated by a locking element 351 and is fixedly connected to the control shaft 30.

Please refer to FIGS. 2 and 3 which are the sectional drawings of a preferred embodiment in the present invention. As shown, inside the inlet channel 13, a rejecting shaft 40 is provided and the lower end of the rejecting shaft 40 is connected to a spring 50. At a normal condition, the rejecting shaft 40 is rejected by the spring 50 to close to a washer 41 thereon so that the pressed atmosphere can not pass through to drive the air tool 10. Then, when the user forces a trigger 19 at the front edge of the handle 11, the trigger 19 may move the rejecting shaft 40 inside the inlet channel 13 to have a tilted angle for passing through the pressed atmosphere. Moreover, the control shaft 30 inside the valve sleeve 14 may have a movement by the user pressing the rejecting portion 35 so as to selectively locate at a first position (as shown in FIG. 2) for coupling the inlet channel 13 to the first conducting portion 32 and communicating with the first inlet air way 131, or at a second position (as shown in FIG. 3) for coupling the inlet channel 13 to the second conducting portion 33 and communicating with the second inlet air way 132. Here, through the separating portion 31, the pressed atmosphere, each time, only can enter the first inlet air way 131 or the second inlet air way 132, so that the purpose of controlling the rotation direction of the air tool 10 can be achieved by the control shaft 30 changing the inlet air way of the air tool 10.

Please refer to FIG. 4 which shows the partial sectional drawing of a preferred embodiment in the present invention. Currently, the air tool 10 is always housed by a plastic material, so that the valve sleeve 14 can not be installed in the air tool 10 by pressing owing to the matching difficulty between the metal material of the valve sleeve 14 and the plastic material. Accordingly, in the present invention, the valve sleeve 14 below the cylinder 15 is fixed with the cylinder 15 by a fixing element 151, which can be a screw, and through the locking and fixing, the valve sleeve 14 can be accurately positioned in the air tool 10. Consequently, the present invention is extremely suitable for being applied to the common-used plastic housed air tool 10.

In the aforesaid, the present invention provides a valve sleeve 14 below the cylinder 15 and a control shaft 30 inside the valve sleeve 14 so that, except controlling the rotation direction of the air tool 10, the operation of the air tool 10 also becomes more convenient. The user, only by one hand, can simultaneously hold the air tool and control the ON/OFF (by pressing trigger 19) and the rotation direction (by pressing the control shaft 30). Furthermore, since the valve sleeve 14 is fixed with the cylinder 15 through a fixing element 151, the present invention is greatly suitable for the plastic housed air tool 10.

It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1. An inlet air way control structure of an air tool, comprising: an inlet channel mounted inside the air tool and connected with a valve sleeve, wherein the valve sleeve is respectively communicated with a first inlet air way, a second inlet air way and a cylinder of an air motor inside the air tool, and the valve sleeve is fixed with the cylinder by a fixing element; a control shaft penetrating the valve sleeve, wherein the control shaft has a separating portion and a first conducting portion and a second conducting portion respectively located in two sides of the separating portion for passing through the air, and the control shaft is capable of moving inside the valve sleeve so as to selectively locate in a first position for coupling the inlet channel to the first conducting portion and communicating with the first inlet air way, or at a second position for coupling the inlet channel to the second conducting portion and communicating with the second inlet air way.
 2. The structure as claimed in claim 1, wherein the first and the second inlet air ways are communicated with the cylinder, and the first and the second inlet air ways are respectively clockwise and counterclockwise inlet air ways.
 3. The structure as claimed in claim 2, wherein the valve sleeve and the control shaft are mounted under the cylinder and are parallel to the cylinder.
 4. The structure as claimed in claim 1, wherein the valve sleeve has plural through holes respectively connecting with the inlet channel and the first and the second inlet air ways.
 5. The structure as claimed in claim 1, wherein the fixing element is a screw. 